[INFO] fetching crate msg-transmitter 0.3.2...
[INFO] checking msg-transmitter-0.3.2 against master#ab869e094a907cc5d19b4080f22eccaf347f1f95 for pr-129604
[INFO] extracting crate msg-transmitter 0.3.2 into /workspace/builds/worker-0-tc1/source
[INFO] validating manifest of crates.io crate msg-transmitter 0.3.2 on toolchain ab869e094a907cc5d19b4080f22eccaf347f1f95
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate msg-transmitter 0.3.2
[INFO] removed 0 missing examples
[INFO] finished tweaking crates.io crate msg-transmitter 0.3.2
[INFO] tweaked toml for crates.io crate msg-transmitter 0.3.2 written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]      Locking 64 packages to latest compatible versions
[INFO] [stderr]       Adding bitflags v1.3.2 (latest: v2.6.0)
[INFO] [stderr]       Adding bytes v0.4.12 (latest: v1.7.1)
[INFO] [stderr]       Adding cfg-if v0.1.10 (latest: v1.0.0)
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[INFO] [stderr]       Adding crossbeam-utils v0.7.2 (latest: v0.8.20)
[INFO] [stderr]       Adding futures v0.1.31 (latest: v0.3.30)
[INFO] [stderr]       Adding hermit-abi v0.3.9 (latest: v0.4.0)
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[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2021
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] be5126f1fef17d6537e7b7c1e25412b0b670a5681d01647a4fe196e1dfcec987
[INFO] running `Command { std: "docker" "start" "-a" "be5126f1fef17d6537e7b7c1e25412b0b670a5681d01647a4fe196e1dfcec987", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "be5126f1fef17d6537e7b7c1e25412b0b670a5681d01647a4fe196e1dfcec987", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "be5126f1fef17d6537e7b7c1e25412b0b670a5681d01647a4fe196e1dfcec987", kill_on_drop: false }`
[INFO] [stdout] be5126f1fef17d6537e7b7c1e25412b0b670a5681d01647a4fe196e1dfcec987
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 79d1b63bd6ae1abe9a7915e3fdc94fd545787a0e5e292debe8a6cdcc69f7aa16
[INFO] running `Command { std: "docker" "start" "-a" "79d1b63bd6ae1abe9a7915e3fdc94fd545787a0e5e292debe8a6cdcc69f7aa16", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2021
[INFO] [stderr]    Compiling proc-macro2 v1.0.86
[INFO] [stderr]     Checking bincode v1.3.3
[INFO] [stderr]    Compiling quote v1.0.37
[INFO] [stderr]    Compiling syn v2.0.77
[INFO] [stderr]    Compiling serde_derive v1.0.209
[INFO] [stderr]     Checking msg-transmitter v0.3.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:161:33
[INFO] [stdout]     |
[INFO] [stdout] 161 |                          -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]     |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 161 |                          -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]     |                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:245:33
[INFO] [stdout]     |
[INFO] [stdout] 245 |                          -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]     |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 245 |                          -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]     |                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/tcp.rs:43:35
[INFO] [stdout]    |
[INFO] [stdout] 43 | ...                   -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 43 |                            -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/tcp.rs:82:63
[INFO] [stdout]    |
[INFO] [stdout] 82 |     pub fn start_client<F>(&self, process_function: F) -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 82 |     pub fn start_client<F>(&self, process_function: F) -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                                               +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/uds.rs:43:35
[INFO] [stdout]    |
[INFO] [stdout] 43 | ...                   -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 43 |                            -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/uds.rs:81:63
[INFO] [stdout]    |
[INFO] [stdout] 81 |     pub fn start_client<F>(&self, process_function: F) -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 81 |     pub fn start_client<F>(&self, process_function: F) -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                                               +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:161:33
[INFO] [stdout]     |
[INFO] [stdout] 161 |                          -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]     |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 161 |                          -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]     |                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:245:33
[INFO] [stdout]     |
[INFO] [stdout] 245 |                          -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]     |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 245 |                          -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]     |                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/tcp.rs:43:35
[INFO] [stdout]    |
[INFO] [stdout] 43 | ...                   -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 43 |                            -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/tcp.rs:82:63
[INFO] [stdout]    |
[INFO] [stdout] 82 |     pub fn start_client<F>(&self, process_function: F) -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 82 |     pub fn start_client<F>(&self, process_function: F) -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                                               +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/uds.rs:43:35
[INFO] [stdout]    |
[INFO] [stdout] 43 | ...                   -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 43 |                            -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/uds.rs:81:63
[INFO] [stdout]    |
[INFO] [stdout] 81 |     pub fn start_client<F>(&self, process_function: F) -> Box<Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 81 |     pub fn start_client<F>(&self, process_function: F) -> Box<dyn Future<Item=(), Error=()> + Send + 'static>
[INFO] [stdout]    |                                                               +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:179:29
[INFO] [stdout]     |
[INFO] [stdout] 179 |                 let rx: Box<Stream<Item=Option<T>, Error=io::Error> + Send> = Box::new(rx.map_err(|_| panic!()));
[INFO] [stdout]     |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 179 |                 let rx: Box<dyn Stream<Item=Option<T>, Error=io::Error> + Send> = Box::new(rx.map_err(|_| panic!()));
[INFO] [stdout]     |                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:179:29
[INFO] [stdout]     |
[INFO] [stdout] 179 |                 let rx: Box<Stream<Item=Option<T>, Error=io::Error> + Send> = Box::new(rx.map_err(|_| panic!()));
[INFO] [stdout]     |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 179 |                 let rx: Box<dyn Stream<Item=Option<T>, Error=io::Error> + Send> = Box::new(rx.map_err(|_| panic!()));
[INFO] [stdout]     |                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:255:17
[INFO] [stdout]     |
[INFO] [stdout] 255 |     let rx: Box<Stream<Item=Option<T>, Error=io::Error> + Send> = Box::new(rx.map_err(|_| panic!()));
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 255 |     let rx: Box<dyn Stream<Item=Option<T>, Error=io::Error> + Send> = Box::new(rx.map_err(|_| panic!()));
[INFO] [stdout]     |                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:255:17
[INFO] [stdout]     |
[INFO] [stdout] 255 |     let rx: Box<Stream<Item=Option<T>, Error=io::Error> + Send> = Box::new(rx.map_err(|_| panic!()));
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 255 |     let rx: Box<dyn Stream<Item=Option<T>, Error=io::Error> + Send> = Box::new(rx.map_err(|_| panic!()));
[INFO] [stdout]     |                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `futures::sync::mpsc`
[INFO] [stdout]   --> examples/master_and_slave.rs:69:9
[INFO] [stdout]    |
[INFO] [stdout] 69 |     use futures::sync::mpsc;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Arc` and `Mutex`
[INFO] [stdout]   --> examples/master_and_slave.rs:70:21
[INFO] [stdout]    |
[INFO] [stdout] 70 |     use std::sync::{Arc, Mutex};
[INFO] [stdout]    |                     ^^^  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `now`
[INFO] [stdout]   --> examples/master_and_slave.rs:60:13
[INFO] [stdout]    |
[INFO] [stdout] 60 |         let now = time::Instant::now();
[INFO] [stdout]    |             ^^^ help: if this is intentional, prefix it with an underscore: `_now`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 8.42s
[INFO] running `Command { std: "docker" "inspect" "79d1b63bd6ae1abe9a7915e3fdc94fd545787a0e5e292debe8a6cdcc69f7aa16", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "79d1b63bd6ae1abe9a7915e3fdc94fd545787a0e5e292debe8a6cdcc69f7aa16", kill_on_drop: false }`
[INFO] [stdout] 79d1b63bd6ae1abe9a7915e3fdc94fd545787a0e5e292debe8a6cdcc69f7aa16